Dry and Wet Ball Mill Syntheses of Sb2Se3 from Its Constituent Elements

Binary antimony selenide (Sb2Se3) compound was synthesized by the mechanical alloying of constituent elements. Both dry and wet mill syntheses methods were applied. Dry milling was done in Ar atmosphere. Wet milling was done using toluene and n-butyl alcohol as a process control agent (PCA). It was found that Sb2Se3 phase was formed using toluene as PCA, whereas usage of n-butyl alcohol led to the formation of mixed phases consisting of Sb2Se3 and unreacted antimony and selenium. Single phase Sb2Se3 was obtained in 6 h and 13 h, respectively, through dry and wet milling, which was confirmed by x-ray diffraction (XRD) and Raman spectroscopy studies. Diffused reflectance spectroscopy studies of as-milled Sb2Se3 yielded direct band gap values of 1.10 eV and 1.18 eV for dry and wet milled samples, respectively. Particle-induced x-ray emission studies revealed that there is no impurity present in the compound and confirmed near stoichiometry. High-resolution transmission electron microscopy observations showed d spacing values of 0.28 nm for dry and toluene milled samples that corresponds to the (221) plane. The milled Sb2Se3 was used as source material and thin films were grown using the e-beam evaporation method. The as-grown films were characterized using XRD, Raman spectroscopy that showed a single phase nature of the films and optical transmission spectra analysis yielding a band gap of 1.29 eV. Electrical resistivity of the films was measured using a two probe method showing a resistivity of 1.6 x 10(7) omega cm. Hot point probe measurement indicated that the as-grown Sb2Se3 films are p-type in nature.